How to access variable dynamically inside an anonymous function/closure?

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To keep the global namespace clean, my JavaScript code is wrapped like this:

(function() {
    /* my code */
})();

Now I have some variables declared in this scope which I want to access using a variable variable name (e.g. the name is 'something' + someVar). In the global scope I'd simply use window['varname'], but obviously that doesn't work.

Is there a good way to do what I want? If not I could simply put those variables inside an object to use the array notation...

Note: eval('varname') is not an acceptable solution. So please don't suggest that.

3

There are 3 answers

0
mVChr On BEST ANSWER

This is a good question because this doesn't point to the anonymous function, otherwise you would obviously just use this['something'+someVar]. Even using the deprecated arguments.callee doesn't work here because the internal variables aren't properties of the function. I think you will have to do exactly what you described by creating either a holder object...

(function() {
  var holder = { something1: 'one', something2: 2, something3: 'three' };

  for (var i = 1; i <= 3; i++) {
    console.log(holder['something'+i]);
  }
})();
3
yuxhuang On
(function(globals) {
    /* do something */
    globals[varname] = yourvar;
})(yourglobals);
1
hugomg On

evil solution/hack: Put the variable you need in a helper object obj and avoid having to change current uses to dot notation by using use with(obj){ your current code... }